This paper presents a random key Differential Evolution algorithm to find the optimal box type sequence and the layer type orientation for a three dimensional single container loading problem. The packing algorithm is based on the layer building approach which groups the boxes of the same type to create layers that are packed into empty spaces in the container. The spaces where layers are represented by maximal empty spaces which are created using difference process. A back bottom left heuristics is used to select the maximal empty space for each layer built. The performance of the DE is tested on seven test cases; each test case consists of 100 instances. The implications of the results show that DE performs well in terms of significant improvement in volume utilization. © 2013 IEEE.